diff options
| -rw-r--r-- | src/qml/doc/src/javascript/dynamicobjectcreation.qdoc | 6 | ||||
| -rw-r--r-- | src/qml/qml/qqmlbuiltinfunctions.cpp | 7 |
2 files changed, 12 insertions, 1 deletions
diff --git a/src/qml/doc/src/javascript/dynamicobjectcreation.qdoc b/src/qml/doc/src/javascript/dynamicobjectcreation.qdoc index 29a4a67460..4342d3bada 100644 --- a/src/qml/doc/src/javascript/dynamicobjectcreation.qdoc +++ b/src/qml/doc/src/javascript/dynamicobjectcreation.qdoc @@ -102,6 +102,12 @@ It is also possible to instantiate components without blocking via the \section2 Creating an Object from a String of QML +\warning Creating objects from a string of QML is extremely slow since the engine has to compile the +passed QML string every time you do it. Furthermore, it's very easy to produce invalid QML when +programmatically constructing QML code. It's much better to keep your QML components as separate +files and add properties and methods to customize their behavior than to produce new components by +string manipulation. + If the QML is not defined until runtime, you can create a QML object from a string of QML using the \l{QtQml::Qt::createQmlObject()}{Qt.createQmlObject()} function, as in the following example: diff --git a/src/qml/qml/qqmlbuiltinfunctions.cpp b/src/qml/qml/qqmlbuiltinfunctions.cpp index 1c718125e4..10d34c683e 100644 --- a/src/qml/qml/qqmlbuiltinfunctions.cpp +++ b/src/qml/qml/qqmlbuiltinfunctions.cpp @@ -1301,10 +1301,15 @@ Each object in this array has the members \c lineNumber, \c columnNumber, \c fil For example, if the above snippet had misspelled color as 'colro' then the array would contain an object like the following: { "lineNumber" : 1, "columnNumber" : 32, "fileName" : "dynamicSnippet1", "message" : "Cannot assign to non-existent property \"colro\""}. -Note that this function returns immediately, and therefore may not work if +\note This function returns immediately, and therefore may not work if the \a qml string loads new components (that is, external QML files that have not yet been loaded). If this is the case, consider using \l{QtQml::Qt::createComponent()}{Qt.createComponent()} instead. +\warning This function is extremely slow since it has to compile the passed QML string every time +it is invoked. Furthermore, it's very easy to produce invalid QML when programmatically constructing +QML code. It's much better to keep your QML components as separate files and add properties and +methods to customize their behavior than to produce new components by string manipulation. + See \l {Dynamic QML Object Creation from JavaScript} for more information on using this function. */ QObject *QtObject::createQmlObject(const QString &qml, QObject *parent, const QUrl &url) const |